Dross compression apparatus are commonly used to recover non-ferrous metals, particularly aluminum, from dross which has been skimmed from a furnace. Aluminum dross is a combination of aluminum metal and aluminum oxides, as well as other possible components such as various oxides, nitrates and carbides. Aluminum dross is a by-product of an aluminum melting operation. Generally the dross floats on top of the molten aluminum metal in the furnace. Aluminum dross may contain anywhere from ten percent to ninety percent aluminum depending on the particular processing technique and the type of furnace. Therefore the dross in an aluminum melting operation includes a significant amount of aluminum metal which is considered a valuable resource to be recovered.
The recovery of aluminum from aluminum dross must also address the problem of the loss of aluminum metal in the dross due to thermiting or thermite reaction, i.e., exothermic oxidation of aluminum metal. It is generally known to provide the compression head of the dross compression apparatus with air or water cooling to reduce the thermiting action and thereby increase the amount of aluminum recovered from the aluminum dross. However, there is a continuing need to be able to remove heat more effectively from the dross compression head to increase the capacity of the dross compression apparatus in recovering aluminum from aluminum dross or other non-ferrous metals from other drosses without the use of water cooling.